Hormone Therapy Does Not Lead to Dementia

Middle-aged women who take hormone replacement therapy to help ease the hot flashes and other symptoms of menopause are not at increased risk of memory loss and dementia years down the road, a new study reports. The findings, published in JAMA Internal Medicine, provide reassurance to the millions of women who use hormone therapy, including the drugs estrogen and progestin, for a limited time to help ease the transition through menopause.

Earlier studies of hormone replacement therapy had raised alarms after the drugs were reported to raise the risk of serious health problems, including an increased risk of heart attacks, breast cancer and dementia. But in those earlier reports, from the Women’s Health Initiative, many of the women were older than 65 and had started taking hormones 20 years past menopause. The reports led doctors to caution that hormone use in women over 65 raises the risk of memory problems and dementia down the road.

The newer data comes from the Women’s Health Initiative Memory Study of Younger Women, or WHIMSY, and focused on women who are younger and who take hormone replacement therapy for a relatively brief period to help ease the passage through menopause. Women in the study ranged in age from 50 to 55 and were taking conjugated equine estrogens, the most common type of hormone replacement therapy in the United States. Women took the hormones for up to seven years

The women were given regular follow-up evaluations to test for signs of memory loss or impending dementia. Most of the women were evaluated for memory problems a decade or so after stopping hormone therapy, in their late 60s.

The study found that these younger women who started taking hormones around the time of menopause did not have an increased risk of damage to the brain.

“In contrast to findings in older postmenopausal women, this study tells women that taking these types of estrogen-based hormone therapies for a relatively short period of time in their early postmenopausal years may not put them at increased risk for cognitive decline over the long term,” said Susan Resnick, Ph.D., chief of the Laboratory of Behavioral Neuroscience at the National Institute on Aging and a co-author of the study. She notes further that while hormones did not present harm, “we did not find any cognitive benefit after long-term follow-up.”

Younger women who took hormones also had no increased risk of heart attack, though they did have a slightly elevated risk of breast cancer.

Deciding whether to begin hormone replacement therapy is a complicated decision that women must discuss with their doctors, and risks and benefits must be carefully weighed. Hormones can have many effects on health, including the health of the brain. This data indicates that at least 10 years out, younger women who take hormones for a limited time need not worry about their effects on memory and thinking skills.